Graziers say they can't afford to move onto the parks without confirmation from the minister, but there is much confusion over the definition of national parks and who exactly has control over them.

Australia uses six main categories to define protected areas ranging from "strict nature reserves" to "protected areas which allow the sustainable use of natural resources".

There are 500 national parks out of a total 9,000 protected areas, and the vast majority are run by State and Territory governments, with some partially funded by the Commonwealth.

But rural lobby group, AgForce, is warning graziers that the Federal Minister for Environment has the last say on access to national parks and will stop grazing if he believes the environment is at risk.

Drought-affected graziers have been allowed onto resources reserves by the Queensland Government, but applications to move onto national parks are still pending.

AgForce spokeswoman Lauren Hewitt says Mr Burke won't clarify whether he plans to overrule State Government legislation that allows grazing in the parks.

She says if the minister does step in graziers will need to get their cattle out of the parks quickly or face possible legal action.

"Our advice is if they're unable to do so for any number of reasons they may face civil liabilities.

"It's quite a difficult position for people who have gone to significant effort to muster and transport cattle there to then turn around and have to do that again in a very quick sense.

"In terms of their mental wellbeing, these are already incredibly stressed graziers who are in drought and significant hardship."

Mr Hughes has an application in to allow cattle onto The Canyon reserve in the Etheridge Shire, but he says they can't afford the risk of the Federal Government taking legal action.

He says he urgently needs to take the pressure off resources at North Head Station.

"The bottom line is we need clarification before this whole thing goes forward. I mean, it shouldn't have got to this point in time. Minister Burke's been very slow in supporting what the State Government has been doing.

"The issues are much bigger than state and federal issues. They need to sort it out, so the livelihoods of people in the grazing industry aren't held in jeopardy any longer."